The solicitor behind a petition protesting at plans to welcome American president Donald Trump on a state visit to Britain says the surge of support for the campaign is “absolutely crazy”.

Graham Guest, who describes himself as “not politically active”, submitted his petition to Parliament several weeks ago and admitted he was surprised when support for it took off yesterday.

Today, signatures soared past the 1 million mark.

Having started Sunday with a few hundred signatures, by 8pm last night 650,000 people had backed the petition, easily passing the 100,000 needed to force MPs to consider it for a debate.

Mr Guest said: “He is a misogynist racist and he just seems to be completely incapable of running the richest, most powerful, country and it is a worry for everyone. I thought a state visit would legitimise his presidency in a way that it shouldn’t be.”

The petition, arguing a state visit from the divisive USA premier would “cause embarrassment” to the Queen, had attracted just a few signatures before taking off yesterday in the wake of a travel ban on Syrian refugees and people from several Muslim-majority countries.

Mr Guest added: “I am not a professional media person, I just did it in my spare time. But these things have a habit of just taking off. I think this immigration ban has angered people a bit and made people get behind it.” Mr Guest said he was “very pleased” the petition could now force a debate in Parliament. He said: “Whether or not the visit will be stopped I don’t know. I am not hugely optimistic but I think it is a way of putting spotlight on it.

“He bans people from coming to America on ridiculous grounds. How does he feel about another country banning him?”